Spinal fusion is a surgical procedure used to correct problems with the small bones
of the spine (vertebrae). It is essentially a "welding" process. The basic idea is
to fuse together the painful vertebrae so that they heal into a single, solid bone.

Spine surgery is usually recommended only when your doctor can pinpoint the source
of your pain. To do this, your doctor may use imaging tests, such as x-rays, computed
tomography (CT), and magnetic resonance imaging (MRI) scans.

Spinal fusion may relieve symptoms of many back conditions, including:

Degenerative disk disease

Spondylolisthesis

Spinal stenosis

Scoliosis

Fracture

Infection

Tumor

Understanding how your spine works will help you better understand spinal fusion.
Learn more about your spine: Spine BasicsSpine Basics (topic.cfm?topic=A00575)

Description

Spinal fusion eliminates motion between vertebrae. It also prevents the stretching
of nerves and surrounding ligaments and muscles. It is an option when motion is the
source of pain, such as movement that occurs in a part of the spine that is arthritic.
The theory is if the painful vertebrae do not move, they should not hurt.

If you have leg pain in addition to back pain, your surgeon may also perform a decompression
(laminectomy). This procedure involves removing bone and diseased tissues that can
put pressure on spinal nerves.

Fusion will take away some spinal flexibility, but most spinal fusions involve only
small segments of the spine and do not limit motion very much.

To help you understand the main terms and abbreviations regarding spinal fusion, a
glossary has been developed: Spinal Fusion GlossarySpinal Fusion Glossary (topic.cfm?topic=A00599)

Lumbar spinal fusion has been performed for decades. There are several different techniques
that may be used to fuse the spine. There are also different "approaches" your surgeon
can take for your procedure.

Your surgeon may approach your spine from the front. This is an anterior approach
and requires an incision in the lower abdomen. (See related article "Anterior Lumbar Interbody FusionAnterior Lumbar Interbody Fusion (topic.cfm?topic=A00595).")

Minimally invasive techniques have also been developed. These allow fusions to be
performed with smaller incisions.

The right procedure for you will depend on the nature and location of your disease.

Bone Grafting

All spinal fusions use some type of bone material, called a bone graft, to help promote
the fusion. Generally, small pieces of bone are placed into the space between the
vertebrae to be fused.

A bone graft is primarily used to stimulate bone healing. It increases bone production
and helps the vertebrae heal together into a solid bone. Sometimes larger, solid pieces
are used to provide immediate structural support to the vertebrae.

In the past, a bone graft harvested from the patient's hip was the only option for
fusing the vertebrae. This type of graft is called an autograft. Harvesting a bone
graft requires an additional incision during the operation. It lengthens surgery and
can cause increased pain after the operation.

Most autografts are harvested from the iliac crest of the hip.

One alternative to harvesting a bone graft is an allograft, which is cadaver bone.
An allograft is typically acquired through a bone bank.

Today, several artificial bone graft materials have also been developed.

Demineralized bone matrices (DBMs). Calcium is removed from cadaver bone to create DBMs. Without the mineral, the bone
can be changed into a putty or gel-like consistency. DBMs are usually combined with
other grafts, and may contain proteins that help in bone healing.

Bone morphogenetic proteins (BMPs). These very powerful synthetic bone-forming proteins promote a solid fusion. They
are approved by the U.S. Food and Drug Administration for use in the spine in certain
situations. Autografts may not be needed when BMPs are used.

Ceramics. Synthetic calcium/phosphate materials are similar in shape and consistency to autograft
bone.

Your surgeon will discuss with you the type of bone graft material that will work
best for your condition and procedure.

Immobilization

After bone grafting, the vertebrae need to be held together to help the fusion progress.
Your surgeon may suggest that you wear a brace.

In many cases, surgeons will use plates, screws, and rods to help hold the spine still.
This is called internal fixation, and may increase the rate of successful healing.
With the added stability from internal fixation, most patients are able to move earlier
after surgery.

As with any operation, there are potential risks associated with spinal fusions. It
is important to discuss all of these risks with your surgeon before your procedure.

Infection. Antibiotics are regularly given to the patient before, during, and often after surgery
to lessen the risk of infections.

Bleeding. A certain amount of bleeding is expected, but this is not typically significant.

Pain at graft site. A small percentage of patients will experience persistent pain at the bone graft
site.

Recurring symptoms. Some patients may experience a recurrence of their original symptoms.

Pseudarthrosis. Patients who smoke are more likely to develop a pseudarthrosis. This is a condition
where there is not enough bone formation. If this occurs, a second surgery may needed
in order to obtain a solid fusion.

Nerve damage. It is possible that the nerves or blood vessels may be injured during these operations.
These complications are very rare.

Blood clots. Another uncommon complication is the formation of blood clots in the legs. These
pose significant danger if they break off and travel to the lungs.

Warning Signs

It is important that you carefully follow any instructions from your doctor relating
to warning signs of blood clots and infection. These complications are most likely
to occur during the first few weeks after surgery.

Warning signs of possible blood clots include the following:

Swelling in the calf, ankle or foot

Tenderness or redness, which may extend above or below the knee

Pain in the calf

Occasionally, a blood clot will travel through the blood stream and may settle in
your lungs. If this happens, you may experience a sudden chest pain and shortness
of breath or cough. If you experience any of these symptoms, you should notify your
doctor immediately. If you cannot reach your doctor, someone should take you to the
hospital emergency room or call 911.
Infection following spine surgery occurs very rarely. Warning signs of infection
include:

Redness, tenderness, and swelling around the wound edges

Drainage from the wound

Pain or tenderness

Shaking chills

Elevated temperature, usually above 100°F if taken with an oral thermometer

If any of these symptoms occur, you should contact your doctor or go to the nearest
emergency room immediately.

Pain Management

After surgery, you will feel some pain. This is a natural part of the healing process.
Your doctor and nurses will work to reduce your pain, which can help you recover from
surgery faster.

Medications are often prescribed for short-term pain relief after surgery. Many types
of medicines are available to help manage pain, including opioids, non-steroidal anti-inflammatory
drugs (NSAIDs), and local anesthetics. Your doctor may use a combination of these
medications to improve pain relief, as well as minimize the need for opioids.

Be aware that although opioids help relieve pain after surgery, they are a narcotic
and can be addictive. Opioid dependency and overdose has become a critical public
health issue in the U.S. It is important to use opioids only as directed by your doctor.
As soon as your pain begins to improve, stop taking opioids. Talk to your doctor if
your pain has not begun to improve within a few days of your surgery.

Rehabilitation

The fusion process takes time. It may be several months before the bone is solid,
although your comfort level will often improve much faster. During this healing time,
the fused spine must be kept in proper alignment. You will be taught how to move properly,
reposition, sit, stand, and walk.

Your symptoms will gradually improve. So will your activity level. Right after your
operation, your doctor may recommend only light activity, like walking. As you regain
strength, you will be able to slowly increase your activity level.

Maintaining a healthy lifestyle and following your doctor's instructions will greatly
increase your chances for a successful outcome.

AAOS does not endorse any treatments, procedures, products, or physicians referenced
herein. This information is provided as an educational service and is not intended
to serve as medical advice. Anyone seeking specific orthopaedic advice or assistance
should consult his or her orthopaedic surgeon, or locate one in your area through
the AAOS "Find an Orthopaedist" program on this website.